Display device

ABSTRACT

A display device is provided and included a cover member curved when viewed in a first axis direction along a first axis; and a display panel disposed on one side of the cover member, wherein the cover member has a first surface facing the display panel and a second surface on the opposite side of the first surface, the first surface is a developable surface in a cross-sectional view in the first axis direction, and the second surface is a three-dimensional curved surface in the cross-sectional view in the first axis direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.15/919,891, filed Mar. 13, 2018, which claims priority from JapaneseApplication No. 2017-053518, filed on Mar. 17, 2017, the contents ofwhich are incorporated by reference herein in its entirety.

BACKGROUND 1. Technical Field

The present disclosure relates to a display device.

2. Description of the Related Art

A display device having a curved surface has been known. For example,Japanese Patent Application Laid-open Publication No. 2015-92422discloses a technique employing a cover glass having a curved surface.In particular, an in-vehicle display device employing the cover glasshaving the curved surface is advantageous in that an automotive interiorpart with curved surfaces and the surface of the display device aresmoothly connected together.

Recent years have seen demands for display devices to have morecharacteristic designs, in some cases. For example, a display surfacemay be desired to be curved about a first axis and also curved about asecond axis orthogonal to the first axis. The display surface is,however, difficult to be curved about two orthogonal axes.

For the foregoing reasons, there is a need for a display device whosedisplay surface appears to be curved about the two orthogonal axes.

SUMMARY

According to an aspect, a display device includes: a cover member curvedwhen viewed in a first axis direction along a first axis; and a displaypanel disposed on one side of the cover member. The cover member has afirst surface facing the display panel and a second surface on theopposite side of the first surface. The first surface forms a straightline and at least a part of the second surface forms a curved line in across-section orthogonal to a second axis that is along a straight lineextending from one end to the other end of the cover member when viewedin the first axis direction.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded perspective view illustrating a display deviceaccording to a first embodiment of the present disclosure;

FIG. 2 is an internal view illustrating a vehicle on which the displaydevice according to the first embodiment is mounted;

FIG. 3 is a perspective view illustrating a cover member according tothe first embodiment;

FIG. 4 is a front view illustrating the cover member according to thefirst embodiment;

FIG. 5 is a plan view illustrating the cover member according to thefirst embodiment;

FIG. 6 is a right side view illustrating the cover member according tothe first embodiment;

FIG. 7 is a cross-sectional view illustrating a cross-section takenalong a line VII-VII′ in

FIG. 5;

FIG. 8 is a schematic diagram for explaining a method for manufacturingthe cover member according to the first embodiment;

FIG. 9 is a perspective view illustrating a cover member according to asecond embodiment of the present disclosure;

FIG. 10 is a plan view illustrating the cover member according to thesecond embodiment;

FIG. 11 is a right side view illustrating the cover member according tothe second embodiment;

FIG. 12 is a cross-sectional view illustrating a cross-section takenalong a line XII-XII′ in

FIG. 10;

FIG. 13 is an exploded perspective view illustrating a display deviceaccording to a third embodiment of the present disclosure;

FIG. 14 is a perspective view illustrating a cover member according tothe third embodiment;

FIG. 15 is a plan view illustrating the cover member according to thethird embodiment;

FIG. 16 is a right side view illustrating the cover member according tothe third embodiment; and

FIG. 17 is a cross-sectional view illustrating a cross-section takenalong a line XVII-XVII′ in FIG. 15.

DETAILED DESCRIPTION

Modes (embodiments) for carrying out the present disclosure will bedescribed in detail with reference to the drawings. The presentdisclosure is not limited by the descriptions of the followingembodiments. The elements described hereunder include those that can beeasily thought of by those skilled in the art and substantially the sameelements. The elements described hereunder may also be combined asappropriate. The disclosure is merely an example, and the presentdisclosure naturally encompasses appropriate modifications maintainingthe gist of the disclosure that is easily conceivable by those skilledin the art. To further clarify the description, a width, a thickness, ashape, and the like of each component may be schematically illustratedin the drawings as compared with an actual aspect. However, this ismerely an example and interpretation of the disclosure is not limitedthereto. The same elements as those described in the drawings that havealready been discussed are denoted by the same reference numeralsthroughout the description and the drawings, and detailed descriptionthereof will not be repeated in some cases. In this disclosure, when anelement A is described as being “on” another element B, the element Acan be directly on the other element B, or there can be one or moreelements between the element A and the other element B.

First Embodiment

FIG. 1 is an exploded perspective view illustrating a display deviceaccording to a first embodiment of the present disclosure. FIG. 2 is aninternal view illustrating a vehicle on which the display deviceaccording to the first embodiment is mounted. As illustrated in FIG. 1,a display device 10 according to the first embodiment includes a displaypanel 5, an adhesive member 3, and a cover member 1. The cover member 1is mounted on the display panel 5 with the adhesive member 3 interposedtherebetween. The display device 10 is mounted, for example, on adashboard 100 of the vehicle, as illustrated in FIG. 2.

The display panel 5 is a liquid crystal panel, for example. A backlightis provided on the back side of the display panel 5. The display panel 5includes a first substrate and a second substrate that are made of glassor the like, and a liquid crystal layer interposed between the firstsubstrate and the second substrate. The display panel 5 displays, forexample, a speedometer, a tachometer, a fuel gauge, and a watertemperature gauge. The display panel 5 is rectangular, for example, whenviewed from the front. The display panel 5 is curved about an axisparallel to short sides thereof, as illustrated in FIG. 1. That is, thedisplay panel 5 is curved when viewed in the short side direction. Bothends in the long side direction of the display panel 5 are closer to theeye-point of a viewer than the center in the short side direction of thedisplay panel 5.

In the following description, an XYZ orthogonal coordinate system isused. The X-axis is parallel to the short sides of the display panel 5.The Y-axis is parallel to a straight line extending from one end to theother end of the display panel 5 when viewed in the X-axis direction.The Z-axis is orthogonal to both the X-axis and the Y-axis. Thedirection along the X-axis is referred to as the X-direction; thedirection along the Y-axis is referred to as the Y-direction; and thedirection along the Z-axis is referred to as the Z-direction.

The adhesive member 3 bonds the cover member 1 to the display panel 5.The adhesive member 3 is a rectangular sheet, for example. The adhesivemember 3 is interposed between the display panel 5 and the cover member1. The adhesive member 3 is placed on top of the display panel 5. Theadhesive member 3 includes an optical adhesive, for example. Theadhesive member 3 transmits light emitted from the display panel 5toward the cover member 1.

FIG. 3 is a perspective view illustrating the cover member according tothe first embodiment. FIG. 4 is a front view illustrating the covermember according to the first embodiment. FIG. 5 is a plan viewillustrating the cover member according to the first embodiment. FIG. 6is a right side view illustrating the cover member according to thefirst embodiment. FIG. 7 is a cross-sectional view illustrating across-section taken along a line VII-VII′ in FIG. 5.

The cover member 1 protects the display panel 5. The cover member 1 ismade of glass, for example. The cover member 1 is disposed on one sideof the display panel 5, and mounted on the display panel 5 with theadhesive member 3 interposed therebetween. The cover member 1 isrectangular when viewed from the front, as illustrated in FIG. 4. Thecover member 1 is curved about the X-axis. That is, the cover member 1is curved when viewed in the X-direction, as illustrated in FIG. 5. Thelight emitted from the display panel 5 reaches the viewer after passingthrough the cover member 1. The viewer sees as if an image is displayedalong a surface of the cover member 1.

As illustrated in FIG. 3, the cover member 1 has a first surface 11 anda second surface 12. The first surface 11 faces the display panel 5, andhas a shape along the display panel 5. When viewed in the X-direction asillustrated in FIG. 5, the first surface 11 forms a circular arccentering on a point on the opposite side of the display panel 5 withrespect to the cover member 1. The second surface 12 is a surface on theopposite side of the surface facing the display panel 5. That is, thesecond surface 12 is a back surface of the first surface 11. When viewedin the X-direction as illustrated in FIG. 5, the second surface 12 formsa circular arc centering on a point on the opposite side of the displaypanel 5 with respect to the cover member 1. As illustrated in FIG. 5,the circular arc formed by the second surface 12 has a curvaturesubstantially equal to that of the circular arc formed by the firstsurface 11 when viewed in the X-direction.

The cross-sectional shape obtained by cutting the cover member 1 along aplane orthogonal to the Y-axis is constant at any positions in theY-direction of the cover member 1. As illustrated in FIG. 7, the firstsurface 11 forms a straight line parallel to the X-axis in thecross-section orthogonal to the Y-axis. The second surface 12 forms acurved line in the cross-section illustrated in FIG. 7. Specifically, inthe cross-section illustrated in FIG. 7, the second surface 12 forms acircular arc centering on a point on the display panel 5 side withrespect to the cover member 1. That is, both ends in the X-direction ofthe second surface 12 are closer to the display panel 5 than the centerin the X-direction of the second surface 12. A distance T1 from thefirst surface 11 to the second surface 12 at the center in theX-direction is larger than a distance T2 from the first surface 11 tothe second surface 12 at the ends in the X-direction.

As described above, the cover member 1 is curved when viewed in theX-direction. The second surface 12 forms the curved line in the sectionillustrated in FIG. 7. In other words, the entire second surface 12 iscurved about the curved line (curved line illustrated in FIG. 5) formedby the first surface 11 when viewed in the X-direction, the curved lineserving as an axis of the curve of the second surface 12.

FIG. 8 is a schematic diagram for explaining a method for manufacturingthe cover member according to the first embodiment. As illustrated inFIG. 8, the cover member 1 is formed by bending an original plate 9about the X-axis. The original plate 9 has a linear outline when viewedin the X-direction. The original plate 9 has a first surface 91 and asecond surface 92. The first surface 91 is a flat surface. The secondsurface 92 is a curved surface curved about the Y-axis.

The display device 10 may not necessarily be mounted on the vehicle, butmay be used in other electronic apparatuses, such as a portableelectronic apparatus. When the display device 10 is mounted on thevehicle, images displayed by the display device 10 are not limited tothe vehicle meters and gauges, but may be a map of a vehicle navigationsystem, for example.

The display panel 5 may be an organic electroluminescent (EL) panel.When the display panel 5 is the organic EL panel, no backlight isneeded. The display panel 5 may have a touch detection function. Thatis, a touchscreen panel may be embedded in the display panel 5 or on asurface of the display panel 5.

The cover member 1 may not necessarily be made of glass. The covermember 1 may be made of a synthetic resin, for example. In thecross-section orthogonal to the Y-axis, the second surface 12 may notnecessarily have a circular arc shape extending from one end to theother end in the X-direction thereof as illustrated in FIG. 7. In thecross-section orthogonal to the Y-axis, at least a part of the secondsurface 12 needs to form a curved line. For example, in thecross-section orthogonal to the Y-axis, the second surface 12 may beconfigured such that a part of the second surface 12 forms a curvedline, and the other part of the second surface 12 forms a straight line.Alternatively, in the cross-section orthogonal to the Y-axis, the secondsurface 12 may be configured such that a part of the second surface 12forms a curved line having a first curvature, and the other part of thesecond surface 12 forms a curved line having a second curvaturedifferent from the first curvature, for example.

As described above, the display device 10 includes: the cover member 1curved when viewed in a direction (X-direction) along a first axis(X-axis); and the display panel 5 disposed on one side of the covermember 1. The cover member 1 has the first surface 11 facing the displaypanel 5 and the second surface 12 on the opposite side of the displaypanel 5. Assume that a second axis (Y-axis) is along a straight lineextending from one end to the other end of the cover member 1 whenviewed in the direction (X-direction) along the first axis (X-axis). Inthis case, in the cross-section orthogonal to the second axis (Y-axis),the first surface 11 forms a straight line, and at least a part of thesecond surface 12 forms a curved line.

This configuration allows the viewer to see as if the entire covermember 1 is curved about the second axis (Y-axis). As a result, thedisplay panel 5 and the cover member 1 appear to be curved about thefirst axis (X-axis), and also curved about the second axis (Y-axis).Consequently, the display device 10 can make a display surface thereofappear to be curved about the two orthogonal axes.

The cross-sectional shape obtained by cutting the cover member 1 with aplane orthogonal to the second axis (Y-axis) is constant. Thisconfiguration suppresses distortion of an image displayed by the displaydevice 10.

In the cross-section orthogonal to the second axis (Y-axis), both endsin the direction (X-direction) along the first axis (X-axis) of thesecond surface 12 are closer to the display panel 5 than the center inthe direction (X-direction) along the first axis (X-axis) of the secondsurface 12. As a result, the display device 10 can make an image appearto project toward the viewer.

When viewed from the second surface 12, both ends thereof in thedirection (Y-direction) along the second axis (Y-axis) are closer to theeye-point of an viewer than the center thereof in the direction(Y-direction) along the second axis (Y-axis). As a result, when thedisplay device 10 is mounted on a vehicle interior part, the displaydevice 10 is smoothly connected to the interior part.

Second Embodiment

FIG. 9 is a perspective view illustrating a cover member according to asecond embodiment of the present disclosure. FIG. 10 is a plan viewillustrating the cover member according to the second embodiment. FIG.11 is a right side view illustrating the cover member according to thesecond embodiment. FIG. 12 is a cross-sectional view illustrating across-section taken along a line XII-XII′ in FIG. 10.

A cover member 1A according to the second embodiment is curved about theX-axis, as illustrated in FIG. 9. That is, the cover member 1A is curvedwhen viewed in the X-direction, as illustrated in FIG. 10. The covermember 1A has a second surface 12A. As illustrated in FIG. 10, thesecond surface 12A forms a circular arc centering on a point on theopposite side of the display panel 5 with respect to the cover member 1Awhen viewed in the X-direction. When viewed in the X-direction, thecircular arc formed by the second surface 12A has a curvaturesubstantially equal to that of the circular arc formed by the firstsurface 11.

The cross-sectional shape obtained by cutting the cover member 1A alonga plane orthogonal to the Y-axis is constant at any positions in theY-direction of the cover member 1A. The second surface 12A forms acurved line in the cross-section illustrated in FIG. 12. Specifically,in the cross-section illustrated in FIG. 12, the second surface 12Aforms a circular arc centering on a point on the opposite side of thedisplay panel 5 with respect to the cover member 1A. That is, the centerin the X-direction of the second surface 12A is closer to the displaypanel 5 than both ends in the X-direction of the second surface 12A. Adistance T1A from the first surface 11 to the second surface 12A at thecenter in the X-direction is smaller than a distance T2A from the firstsurface 11 to the second surface 12A at the ends in the X-direction.

As described above, the cover member 1A is curved when viewed in theX-direction, and the second surface 12A forms the curved line in thecross-section illustrated in FIG. 12. In other words, the entire secondsurface 12A is curved about the curved line (curved line illustrated inFIG. 10) formed by the first surface 11 when viewed in the X-direction,the curved line serving as an axis of the curve of the second surface12A.

Third Embodiment

FIG. 13 is an exploded perspective view illustrating a display deviceaccording to a third embodiment of the present disclosure. FIG. 14 is aperspective view illustrating a cover member according to the thirdembodiment. FIG. 15 is a plan view illustrating the cover memberaccording to the third embodiment. FIG. 16 is a right side viewillustrating the cover member according to the third embodiment. FIG. 17is a cross-sectional view illustrating a cross-section taken along aline XVII-XVII′ in FIG. 15.

A display device 10B according to the third embodiment includes adisplay panel 5B and a cover member 1B. The display panel 5B is curvedabout the X-axis, as illustrated in FIG. 13. That is, the display panel5B is curved when viewed in the X-direction. When viewed from theviewer, the center in the long side direction of the display panel 5B iscloser to the eye-point of the viewer than ends in the long sidedirection of the display panel 5B.

The cover member 1B is curved about the X-axis, as illustrated in FIG.14. That is, the cover member 1B is curved when viewed in theX-direction, as illustrated in FIG. 15. The cover member 1B has a firstsurface 11B and a second surface 12B. The first surface 11B faces thedisplay panel 5B, and has a shape along the display panel 5B. Asillustrated in FIG. 15, each of the first surface 11B and the secondsurface 12B forms a circular arc centering on a point on the displaypanel 5B side with respect to the cover member 1B when viewed in theX-direction. When viewed in the X-direction, the circular arc formed bythe second surface 12B has a curvature substantially equal to that ofthe circular arc formed by the first surface 11B.

The cross-sectional shape obtained by cutting the cover member 1B alonga plane orthogonal to the Y-axis is constant at any positions in theY-direction of the cover member 1B. As illustrated in FIG. 17, the firstsurface 11B forms a straight line parallel to the X-axis in thecross-section orthogonal to the Y-axis. The second surface 12B forms acurved line in the cross-section illustrated in FIG. 17. Specifically,the second surface 12B forms a circular arc centering on a point on thedisplay panel 5B side with respect to the cover member 1B in thecross-section illustrated in FIG. 17. That is, the center in theX-direction of the second surface 12B is closer to the eye-point of theviewer than the ends in the X-direction of the second surface 12B. Adistance T1B from the first surface 11B to the second surface 12B at thecenter in the X-direction is larger than a distance T2B from the firstsurface 11B to the second surface 12B at the ends in the X-direction.

As described above, the cover member 1B is curved when viewed in theX-direction, and the second surface 12B forms the curved line in thecross-section illustrated in FIG. 17. In other words, the overall secondsurface 12B is curved about the curved line (curved line illustrated inFIG. 15) formed by the first surface 11B when viewed in the X-direction,the curved line serving as an axis of the curve of the second surface12B.

The present disclosure can naturally provide other advantageous effectsthat are provided by the aspects described in the embodiments above andare clearly defined by the description in the present specification orappropriately conceivable by those skilled in the art.

What is claimed is:
 1. A display device comprising: a cover membercurved when viewed in a first axis direction along a first axis; and adisplay panel disposed on one side of the cover member, wherein thecover member has a first surface facing the display panel and a secondsurface on the opposite side of the first surface, the first surface isa developable surface in a cross-sectional view in the first axisdirection, and the second surface is a three-dimensional curved surfacein the cross-sectional view in the first axis direction.
 2. The displaydevice according to claim 1, wherein the first surface forms a straightline in the first axis direction and a curved line in a second axisdirection orthogonal to the first axis direction.
 3. The display deviceaccording to claim 1, wherein at least a part of the second surfaceforms a curved line in the first axis direction and a second axisdirection orthogonal to the first axis direction.
 4. The display deviceaccording to claim 1, wherein a cross-sectional shape obtained bycutting the cover member along a plane orthogonal to a second axis isconstant at any positions in a second axis direction along the secondaxis.
 5. The display device according to claim 1, wherein, in across-section orthogonal to a second axis, both ends of the secondsurface in the first axis direction are closer to the display panel thana center of the second surface in the first axis direction.
 6. Thedisplay device according to claim 1, wherein, when viewed from thesecond surface, both ends of the second surface in a second axisdirection along a second axis are closer to an eye-point of a viewerthan a center of the second surface in the second axis direction.
 7. Adisplay device comprising: a cover member curved when viewed in a firstaxis direction along a first axis; and a display panel disposed on oneside of the cover member, wherein the cover member has a first surfacefacing the display panel and a second surface on the opposite side ofthe first surface, the first surface forms a straight line and at leasta part of the second surface forms a curved line in a cross-sectionorthogonal to a second axis that is along a straight line extending fromone end to the other end of the cover member when viewed in the firstaxis direction, and the second surface forms a circular arc when viewedin the first axis direction.
 8. The display device according to claim 7,wherein a cross-sectional shape obtained by cutting the cover memberalong a plane orthogonal to the second axis is constant at any positionsin a second axis direction along the second axis.
 9. The display deviceaccording to claim 7, wherein, in the cross-section orthogonal to thesecond axis, both ends of the second surface in the first axis directionare closer to the display panel than a center of the second surface inthe first axis direction.
 10. The display device according to claim 8,wherein, when viewed in the cross-section orthogonal to the second axis,both ends of the second surface in the first axis direction are closerto the display panel than a center of the second surface in the firstaxis direction.
 11. The display device according to claim 7, wherein,when viewed from the second surface, both ends of the second surface ina second axis direction along the second axis are closer to an eye-pointof an viewer than a center of the second surface in the second axisdirection.
 12. The display device according to claim 8, wherein, whenviewed from the second surface, both ends of the second surface in thesecond axis direction are closer to an eye-point of a viewer than acenter of the second surface in the second axis direction.
 13. Thedisplay device according to claim 9, wherein, when viewed from thesecond surface, both ends of the second surface in a second axisdirection along the second axis are closer to an eye-point of a viewerthan a center of the second surface in the second axis direction. 14.The display device according to claim 10, wherein, when viewed from thesecond surface, both ends of the second surface in the second axisdirection are closer to an eye-point of a viewer than a center of thesecond surface in the second axis direction.